Collaborative Research: Extending leaf functional trait ecology to leaf symbionts

所有树木的健康叶子内都生活着丰富多样的真菌。这些“真菌内生菌”（endo，内部；phyte，植物）对于在压力条件下增强植物健康非常重要。然而，形成不同植物物种中不同内生菌群落的因素尚不清楚。该项目的总体目标是将内生真菌纳入我们对热带植物生态学的理解中，特别关注叶子性状、植物生产力以及植物抵御攻击叶子的昆虫和病原体的能力之间的关系。 提高我们对内生真菌的了解非常重要，因为它们影响植物的生产力和对干旱和疾病等环境胁迫的抵抗力，包括具有经济重要性的植物。研究结果将有助于利用内生菌来减轻植物对快速变化的世界的反应，并在可持续农业和森林管理方面具有潜在的应用前景。 该项目还将支持对本科生和研究生进行跨学科研究的培训，包括代表性不足群体的学生，为 K-12 教师和高中生提供指导研究经验，并为公众宣传做出贡献。在叶子性状和内生菌高度多样化的热带森林中，该项目将测试以下假设：(1) 叶子中的内生菌群落随生长与持久策略相关的叶子性状而变化； (2)内生菌会影响叶片和植株的功能； (3) 内生菌对植物防御的贡献将随着叶片性状的变化而变化； （4）通过整合这些叶共生体，可以极大地了解植物的生长与持久策略。研究方法包括现场观察和实验以及生物测定。计划进行一项田间实验，对 12 个重点物种的内生菌群落进行操作。此外，来自这 12 个物种的叶子将被引入切叶蚁中，以测试寿命较长的物种是否对切叶蚁的吸引力较小，以及这是否是由内生菌负载介导的。此外，将病原体引入 12 个焦点物种，以测定内生菌含量高的叶子的损害是否会较低。

Abundant and diverse fungi live inside healthy leaves of all trees. These 'fungal endophytes' (endo, inside; phyte, plant) can be important in enhancing plant health under stressful conditions. However, the factors that shape the diverse communities of endophytes found in different plant species are not well understood. This project's overall goal is to integrate fungal endophytes into our understanding of tropical plant ecology, with a special focus on the relationships among leaf traits, plant productivity, and the ability of plants to defend against insects and pathogens that attack leaves. Improving our understanding of fungal endophytes is important since they influence plant productivity and resistance to environmental stresses such as drought and disease, including for plants of economic importance. Results will facilitate use of endophytes in mitigating plant responses to a rapidly changing world, with potential applications in sustainable agriculture and forest management. This project will also support the training of undergraduate and graduate students in interdisciplinary research, including students of under-represented groups, provide mentored research experiences for K-12 teachers and for high school students, and contribute to public outreach.In the context of tropical forests, where leaf traits and endophytes are highly diverse, this project will test the hypotheses that (1) endophyte communities in leaves vary in relation to leaf traits associated with growth vs. persistence strategies; (2) endophytes will influence leaf and plant functions; (3) contribution of endophytes to plant defense will vary as a function of leaf traits; and (4) understanding growth vs. persistence strategies of plants can be informed greatly by integration of these foliar symbionts. The research approach involves field observations and experiments as well as bioassays. A field experiment is planned where endophyte communities are manipulated in 12 focal species. Additionally, leaves from these same 12 species will be introduced to leaf cutter ants to test whether longer lifespan species are less attractive to leaf cutter ants, and whether this will be mediated by endophyte load. Furthermore, pathogens will be introduced to the 12 focal species to assay if damage will be lower in leaves with high endophyte loads.